Park at Place Buissière in Apprieu.
(S/E) Start on the Route de Lyon towards Plambois, immediately after the restaurant Le Régence, turn left onto Chemin du Calvaire and you will soon reach Impasse du Sapin.
(1) Turn right into this cul-de-sac and continue along Chemin du Guichard until you reach a path at the edge of the forest.
(2) Continue along this path at the edge of the woods. Then make a circular turn and cross a small stream to reach Plan Bois at the crossroads of the Route des Hauts de Plambois.
(3) Turn right, cross the village of Plan Bois and you will find yourself at the edge of another wood.
(4) Walk along the edge of this wood and turn left in a circular route to stay on the road leading to Combe Vieille.
(5) Enter the woods here and continue climbing up to the ridge. You will reach a crossroads with several paths.
(6) Keep left on the ridge, where the slope levels out and becomes almost flat, leading to the summit of Mont Follet.
(7) Continue straight ahead and you will soon reach another crossroads with several directions. Take the path straight ahead towards the telecommunications tower. You will reach a tarmac road at Plan du Rey.
(8) Turn right onto this road, pass in front of the tower and continue keeping to the left until you reach the crossroads before the Thivoley ponds.
(9) Turn left and walk along the ponds. Pass between the5th and6th ponds and walk along the right-hand side of the latter.
(10) Continue along the path heading due east until you reach a T-junction.
(11) Take the path on the right and keep right at the following crossroads. You will then reach the crossroads you passed on the way to Chemin du Calvaire.
(1) Continue straight ahead to return to the Place Buissière car park (S/E).
This hike should not be attempted at this time of year or in spring, as after the ponds the path is impassable due to water. We had to go through the forest to avoid them, with a lot of tree felling and no markings on the trees. You have to walk with your head torch on to find the right path, and the descent through the leaves is very difficult due to slipping on unstable stones. Do this hike when there is no sun, as most of it is in fog. (I saw people on this trail.)
Do this hike in March, it's a real pain, lots of water and mud on the paths, the climb to Combe Vieille has turned into a stream and is very slippery, after the ponds it's the same again, paths full of water, we had to go through the forest, climbing over fallen trees to get through and pick up the path further on. Don't do it at the end of winter.